LEEUWENHOEK, Antoni (Anton, Antonie) van

Scientist. Van Leeuwenhoek served as a minor civil servant in his native city Delft. He is the inventor of the microscope, with which he discovered microorganisms such as bacteria and spermatozoa. For half a century, he described his discoveries in hundreds of letters to the English Royal Society, to which he was introduced by his fellow townsman, physician Reinier de Graaf (1641–1673).